/* *****************************************************************
    MESQUITE -- The Mesh Quality Improvement Toolkit

    Copyright 2006 Sandia National Laboratories.  Developed at the
    University of Wisconsin--Madison under SNL contract number
    624796.  The U.S. Government and the University of Wisconsin
    retain certain rights to this software.

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public License
    (lgpl.txt) along with this library; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    (2010) kraftche@cae.wisc.edu

  ***************************************************************** */

/** \file AWUntangleBeta.cpp
 *  \brief
 *  \author Jason Kraftcheck
 */

#include "Mesquite.hpp"
#include "AWUntangleBeta.hpp"
#include "MsqMatrix.hpp"
#include "TMPDerivs.hpp"
#include "TMPCommon.hpp"

namespace MBMesquite
{

std::string AWUntangleBeta::get_name() const
{
    return "AWUntangleBeta";
}

AWUntangleBeta::~AWUntangleBeta() {}

const int P = 3;

template < unsigned DIM >
inline bool AWUntangleBeta::eval( const MsqMatrix< DIM, DIM >& A, const MsqMatrix< DIM, DIM >& W, double& result )
{
    const double alpha = det( A );
    const double omega = det( W );
    double tmp         = alpha - mGamma * omega;
    tmp                = fabs( tmp ) - tmp;
    result             = tmp;
    for( int i = 1; i < P; ++i )
        result *= tmp;

    return true;
}

template < unsigned DIM >
inline bool AWUntangleBeta::grad( const MsqMatrix< DIM, DIM >& A,
                                  const MsqMatrix< DIM, DIM >& W,
                                  double& result,
                                  MsqMatrix< DIM, DIM >& deriv )
{
    const double alpha = det( A );
    const double omega = det( W );
    double tmp         = 2 * ( mGamma * omega - alpha );
    if( tmp < 0.0 )
    {
        result = 0.0;
        deriv  = MsqMatrix< DIM, DIM >( 0.0 );
        return true;
    }

    double prod = 1.0;
    for( int i = 1; i < P; ++i )
        prod *= tmp;
    result = prod * tmp;

    deriv = -2 * P * prod * transpose_adj( A );
    return true;
}
/*
template <unsigned DIM> inline
bool AWUntangleBeta::hess( const MsqMatrix<DIM,DIM>& A,
                           const MsqMatrix<DIM,DIM>& W,
                           double& result,
                           MsqMatrix<DIM,DIM>& deriv,
                           MsqMatrix<DIM,DIM>* second )
{
  result = det(A) - det(W);
  deriv = transpose_adj(A);
  set_scaled_outer_product( second, 2.0, deriv );
  pluseq_scaled_2nd_deriv_of_det( second, 2*result, A );
  deriv *= 2*result;
  result *= result;
  return true;
}
*/
TMP_AW_TEMPL_IMPL_COMMON_NO2ND( AWUntangleBeta )

}  // namespace MBMesquite
